Disappearing Ice

disappearing

ice

WorldWise

WorldWise

ÂŽ

Content-based Learning

WorldWise

Content-based Learning

Written by Kerrie Shanahan

Disappearing Ice

Disappearing Ice

Science

Informational text types: Explanation/Description Level: M (28)* Next Generation Science Standards: Grade 2 • ESS2.A Earth materials and systems • ESS2.C The roles of water in Earth’s surface processes Key concepts • The amount of pack ice in the Arctic is decreasing.

• Many animals that live in the Arctic are struggling to survive because there is less pack ice.

Written by Kerrie Shanahan Series Consultant: Linda Hoyt

Text features • Chapters with headings and sub-headings, map, diagram, captioned photographs, fact boxes, glossary, index Reading strategy • Linking graphics and visual images to running text

© 2020 EC Licensing Pty Ltd. This work is protected by US copyright law, and under international copyright conventions, applicable in the jurisdictions in which it is published. All rights reserved. The trademark “Flying Start to Literacy” and Star device is a registered trademark of EC Licensing Pty Ltd in the US. The trademark “WorldWise Content-based Learning” and Star device is owned by EC Licensing Pty Ltd. Purchasers of this book may have certain rights under applicable copyright law to copy parts of this book. Purchasers must make the necessary enquiries to ascertain whether, and to what extent, they have any such right in the jurisdiction in which they will be using the book.

Photograph on cover © Incredible Arctic | Shutterstock; p.1 © MrPhotoMania | Shutterstock; p.2 (t) © Patricia Hamilton | Getty Images, (bl) © Enrique Aguirre | Shutterstock, (br) © Daviesrobin | Dreamstime.com; p.4, p.7 (bl) © Paul Nicklen | Getty Images; p.4-5, p.6-7, p.8-9, p.10-11, p.12-13, p.14-15, p.16-17, p.18-19. p.20 © Incredible Arctic | Shutterstock; p.5 © jo Crebbin | Shutterstock; p.6 (l) © NikKulch | Shutterstock, (r) © Dave Jones | Dreamstime.com; p.7 (t) © Vaclav Sebek | Shutterstock, (ml) © Dolores Harvey | Shutterstock, (mr) © Mikelane45 | Dreamstime.com, (br) © Valentina Photo | Shutterstock; p.8-9 © Freddycat | Dreamstime.com; p.9 © Maksimilian | Shutterstock; p.10-11 © Erectus | Dreamstime.com; p.12 (t) © vladsilver | Shutterstock, (b) © Brian J. Skerry | Getty Images, (r) © Kakigori Studio | Shutterstock; p.13 (t) © Sergey Uryadnikov | Shutterstock, (m) © Mutabor5 | Dreamstime.com, (b) © Dolores Harvey | Shutterstock; p.14 (t) © Daniel Cox | Getty Images, (b) © NaturesMomentsuk | Shutterstock; p.15 (t) © Plunne | Dreamstime.com, (b) © Christopher Wood | Shutterstock; p.16 (t) © Simon Dux | Shutterstock, (b) © Rattiya Thongdumhyu | Shutterstock; p.17 © Lavrushka | Shutterstock, © Xenia Snowstorm | Shutterstock, © Daria Riabets | Shutterstock, © Hennadii H | Shutterstock, © KittyVector | Shutterstock, © Nagel Photography | Shutterstock; p.18 (t) © vladsilver | Shutterstock, (b) © MB Photography | Getty Images

Developed by Eleanor Curtain Publishing Printed and bound in China through Colorcraft Ltd, Hong Kong Distributed in the USA by Okapi Educational Publishing Inc. Phone: 866-652-7436 Fax: 800-481-5499 Email: info@myokapi.com www.myokapi.com www.worldwise-reading.com ISBN: 978-1-76086-774-4 1 2 3 4 5 6 7 8 9 10 20 21 22 23 24 25

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WorldWise

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* Levels indicated by letters are Okapi’s unique measurements, comparable to the Guided Reading levels of Fountas and Pinnell. Numerical levels in parentheses align with DRA.

WorldWise

™

Content-based Learning

Contents Introduction 4 Chapter 1 The Arctic: An icy home 6 Ice in the Arctic 8

Chapter 2 A changing habitat 10 Shrinking pack ice 10

Chapter 3 Impact on animals 12 Staying safe 12 Moving around 14 Hunting for food 15 Food problems 16

Conclusion 18 Glossary 19 Index 20

Introduction A polar bear stands on a large sheet of ice in the Arctic. She is hunting. Her sense of smell tells her that seals are not far away. The seals are hunting, too.

They feed on Arctic cod, which swim underneath the massive sheets of ice that cover the ocean.

Sadly, this polar bear is struggling to find enough food – her icy home is in trouble. The ice is melting, causing many problems for this polar bear, and for most animals of the Arctic.

4

5

Chapter 1

Animals of the Arctic

The Arctic: An icy home

Polar bear

The Arctic is the most northern part of the earth.

It is a cold, harsh place, made up of land and water.

The water in the ocean is so cold that it freezes, and some of the ocean stays covered in large sheets of ice all year round.

The land in the Arctic is covered in ice and snow most of the year. No trees grow here because it is too cold.

But the animals that live in the Arctic are able to survive in this frozen world. They have ways of getting the food

Seal

Arctic fox

Narwhal

Arctic cod

they need, and to stay safe from predators.

Arc

6

tic Circle

7

The Arctic: An icy home

Ice in the Arctic The ice floating on top of the ocean is called pack ice.

The amount of pack ice changes as

Pack ice is not connected to land or the ocean floor. It

the weather changes. In summer, the

is moved around by the wind and water currents.

pack ice sheets break up into smaller

Icy fact Most sheets of pack ice are between one and six feet thick, but some can be up to 20Â feet thick.

pieces, which slowly melt away.

8

9

Chapter 2

A changing habitat The earth is becoming warmer, the climate is changing, and the Arctic is changing, too.

Shrinking pack ice The amount of pack ice in the Arctic is shrinking.

Because the Arctic is warmer than it used to be, more pack ice is melting earlier each summer. Winters are not as cold as they used to be, and there is less pack ice.

What happens to Arctic animals when there is less pack ice?

Did you know?

Some scientists estimate that in just over 20Â years there might be no ice in the Arctic during summer.

10

11

The female ringed seal makes a den

Chapter 3

Impact on animals Arctic animals need pack ice. Some use it to stay safe from predators, some move around on the ice to find a mate, and some use it to hunt for food.

in the ice before she gives birth to her pup. The pup then stays in the icy den where it is safe. Now that the ice melts earlier, the pup has less time in its safe den.

Having less ice is affecting Arctic animals. Some are in danger of becoming extinct.

Staying safe Orcas

Some animals use pack ice to keep safe from predators.

Narwhals swim into cracks between the ice sheets

Narwhals

to hide from orcas. But because there is now less pack ice, narwhals have fewer places to hide.

They are more likely to be eaten by orcas or whales.

Did you know?

How big are narwhals?

Human

12

Narwhal

Orca

Ringed seals have claws on their flippers that they use to dig holes in the ice. Snow forms a cover over the hole to make a safe, icy den.

Ringed seal

13

Impact on animals

Hunting for food Polar bears use the pack ice to hunt for seals to eat. They wait on top of the ice as the seals swim underneath. When a seal comes to the surface to breathe, the waiting polar bear catches it.

But because the ice is melting earlier, polar bears have less time to hunt for food.

Moving around Pack ice creates a huge area that animals

Did you know?

can move around on. But once the ice

Polar bears eat seals because seals are high in fat.

The food the polar bears eat on land, when the ice has melted, is not high in fat.

melts, the animals can no longer do this.

Arctic foxes use the pack ice like a bridge to get from place to place. Now that the ice is melting faster and earlier, foxes sometimes get cut off from other foxes. This makes it more difficult to find a mate, and so fewer pups are born.

14

15

Impact on animals

Food problems

Arctic food chain

Arctic animals have difficulty finding food when there is less pack ice. The food chain

Polar bear

is affected.

Algae are tiny living things that grow on the

Pack ice

bottom of pack ice. Algae are eaten by other tiny living things called zooplankton. But

Algae

there is a problem.

Ringed seal

There is not as much algae growing now because there is less pack ice for it to grow on.

Zooplankton

So the zooplankton have fewer algae to feed on.

This means there are fewer zooplankton drifting in the water. Arctic cod feed on zooplankton, but now there is less food, and

Zooplankton

Arctic cod

the cod may not grow and breed.

With fewer Arctic cod in the ocean, the seals do not have as much food, so their numbers are dropping.

And without seals, the polar bears do not have enough high-fat food. Without this high-fat food, they become too thin and cannot have cubs.

16

Polar bear facts • There are about 20,000–25,000 polar bears in the wild.

• Polar bears are listed as in danger. This means they are likely to become extinct if things don’t improve for them.

17

Conclusion

Glossary

The Arctic is changing. The amount of pack

algae tiny living things that are neither plants nor

ice is shrinking, and this is a problem for the

animals; mostly found in water

animals that need the ice to survive.

But there are people who are working to help these animals. Scientists are studying the impact of melting Arctic ice. They are also working on ways to slow down climate change.

And this will hopefully slow down the rate that Arctic pack ice is disappearing.

Arctic the icy-cold area of the world that surrounds the North Pole climate what the weather conditions are usually like, year after year, in a particular place climate change when the usual patterns of the weather change extinct when a group of living things no longer has any living members on Earth ice sheets large, thick areas of ice pack ice ice that floats on top of ocean water and is not connected to land or to the ocean floor predators animals that get food by killing and eating other animals water currents the natural movements of water that usually follow a certain pattern zooplankton tiny, floating animals that live in water

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19

WorldWise: Content-based Learning | Curriculum-linked titles

Index

Guided Reading Levels Level K (20)*

Level L (24)*

Level M (28)*

algae 16, 17, 19

Next Generation Science

A River’s Journey

Amazing Lifetimes

Animals of the African Grasslands

Cracking, Sinking, and Bubbling Over

Deserts of the World

Bridges

Heating and Cooling: How Do Things Change?

Monster Machines

Champions of the Animal World

How Do Plants Grow Here?

Robots

Disappearing Ice

climate 10, 18, 19

Killer Plants

Sharing Our Yard

Majestic Mountains

food chain 16, 17

Making Work Easy

Side by Side

Silkworms

narwhals 7, 12

Saving the Oceans

Summer in Antarctica

The Changing Shape of the Land

Why We Need Rainforests

Weather

What Is It?

Eleanor Roosevelt

Could You Live Here?

A City Grows

Let’s Vote!

Ponchos, Parkas, and Baseball Caps

By Land, Sea, and Air

predator/s 6, 12, 19

Making Our Cities Green

Reach for the Sky

The Port

scientists 11, 18

We Got Tickets!

Skyscrapers and Elevators

When Disaster Strikes

Arctic cod 4, 7, 16, 17 Arctic fox 7, 14

orcas 12 polar bears 4, 7, 15, 16, 17

seal/s 4, 7, 13, 15, 16, 17 summer 10, 11 winter 10 zooplankton 16, 17

20

C3 Social Studies

WorldWise: Content-based learning | Curriculum-linked titles Next Generation Science

C3 Social Studies

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